Bicycle and spider capable of measuring power

ABSTRACT

A bicycle capable of measuring power is disclosed. The bicycle comprises a spider including a torque input section and at least one torque output section; a crank assembly coupled with the spider through the torque input section and applying an input torque to the spider; a chainring mounted to the spider through the at least one torque output section and receiving an output torque from the spider; a gauge disposed and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section; and a circuitry coupled to the gauge and receiving a signal from the gauge.

RELATED APPLICATION

This application is a continuation-in-part of U.S. patent application Ser. No. 16/542,404, filed on Aug. 16, 2019, entitled “BICYCLE AND SPIDER CAPABLE OF MEASURING POWER,” the disclosure of which is hereby incorporated by reference herein.

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates to a bicycle capable of measuring power, and, more particularly, to a spider of the bicycle capable of measuring power transmitted through the spider.

Description of Related Art

Riding a bicycle is an activity that a cyclist applies force on pedals exceeding the opposing force of friction from the bicycle tires and the air resistance or other force (such as gravity, inertia, and etc.) and drives the bicycle moving forward. Work done by the cyclist causes the crankset to rotate, and the energy is transferred through the crankset to the kinetic energy of the bicycle via the chain. For training and racing purpose, it is important to measure or monitor the pedaling force or power during cycling so as to track and adjust cyclist's pedaling cadence instantly or modify a succeeding training program.

A bicycle with strain gauges is commercially provided to measure the power generated from the cyclist by ways of measuring the deformation strain applying on various components. Generally, the strain gauges are placed in/on one or both pedals, one or both crank arms, an axle in the bottom bracket, or a spider of the crankset where the force transmitted through the at least one components mentioned above can be measured. For example, U.S. Pat. No. 8,505,393, titled “Crankset Based Bicycle Power Measurement,” employs a pair of strain gauges placed on the spider and arranged at opposing 45 degree angles on a single gauge substrate (see FIGS. 2 and 4) to measure shear strain occurred on the spider. In addition, U.S. Pat. No. 8,117,923, titled “Bicycle Bottom Bracket Force Sensor,” employs two pairs of strain gauges placed on the bottom bracket and each pair of strain gauges are arranged in a X-shape (see FIGS. 7, 9 and 16) to measure shear strain occurred on the bottom bracket. However, the existing strain gauge measuring techniques are not straightforward and may be affected by other non-effective so that the measurement has less precision and accuracy. In some cases, bicycle's component to which strain gauges are attached needs to be reshaped or even weaken part of the structure for magnifying the applied strain and thus getting a better measurement result. Accordingly, the structure strength or integrity of the reshaped part is quite reduced further. Therefore, other improvements for bicycle power measurements are sufficient required.

SUMMARY OF THE INVENTION

It is therefore an object of the present invention to provide a bicycle or a spider capable of simply, precisely and accurately measuring power generated from a cyclist.

In one aspect of the present invention, the bicycle comprises a spider including a torque input section and at least one torque output section; a crank assembly coupled with the spider through the torque input section and applying an input torque to the spider; a chainring mounted to the spider through the at least one torque output section and receiving an output torque from the spider; at least one gauge disposed and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section; and a circuitry coupled to the at least one gauge and receiving a signal from the at least one gauge.

In another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent or an internal common tangent to the torque input section and the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent and an internal common tangent to a circle with a radius of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section and a circle with a radius of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the spider has at least one arm portion and a central portion, and the torque input section is located at the central portion and the at least one torque output section is located at the at least one arm portion, and wherein the at least one arm portion is asymmetric with respect to a line from a center of the torque input section to a center of the at least one torque output section.

In yet another aspect of the present invention, the spider has at least one arm portion and a central portion, and the at least one arm portion does not radially extend from the central portion.

In yet another embodiment of the present invention, the at least one arm portion is clockwise or counterclockwise obliquely extending from the central portion.

In yet another aspect of the present invention, an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.

In yet another aspect of the present invention, the at least one gauge is attached on a flat surface of the spider, and a normal line of the flat surface forms an angle with a plane of the chainring and the angle ranges from 0 to 180 degrees.

In yet another aspect of the present invention, the flat surface of the spider is formed on a convex or concave of the spider and aligned with the tangential direction or the quasi-tangential direction.

In yet another aspect of the present invention, pure tensile or compressive stress occurs on where the at least one gauge is disposed.

In one aspect of the present invention, the spider comprises a central portion including a torque input section; at least one arm portion including at least one torque output section and outward extending from the central portion; and at least one gauge, disposed and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section and generating a signal in response to torque transmission from the torque input section to the at least one torque output section.

In another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent or an internal common tangent to the torque input section and the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent and an internal common tangent to a circle with a radius of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section and a circle with a radius of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the at least one arm portion is asymmetric with respect to a line from a center of the torque input section to a center of the at least one torque output section.

In yet another aspect of the present invention, the at least one arm portion does not radially extend from the central portion.

In yet another embodiment of the present invention, the at least one arm portion is clockwise or counterclockwise obliquely extending from the central portion.

In yet another aspect of the present invention, an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.

In yet another aspect of the present invention, the at least one gauge is attached on a flat surface of the spider, and a normal line of the flat surface forms an angle with a main plane of the spider and the angle ranges from 0 to 180 degrees.

In yet another aspect of the present invention, the flat surface of the spider is formed on a convex or concave of the spider and aligned with the tangential direction or the quasi-tangential direction.

In yet another aspect of the present invention, pure tensile or compressive stress occurs on where the at least one gauge is disposed.

Besides, it is another object of the present invention to provide a lightweight bicycle or a lightweight spider capable of simply, precisely and accurately measuring power generated from a cyclist.

In one aspect of the present invention, the bicycle comprises a spider including a torque input section, at least one torque output section, and at least one compartment which is located between the torque input section and the at least one torque output section; a crank assembly coupled with the spider through the torque input section and applying an input torque to the spider; a chainring mounted to the spider through the at least one torque output section and receiving an output torque from the spider; at least one gauge disposed and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section; and a circuitry coupled to the at least one gauge and receiving a signal from the at least one gauge.

In yet another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent or an internal common tangent to the torque input section and the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent and an internal common tangent to a circle with a radius of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section and a circle with a radius of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the spider has a central portion and at least one arm portion which is clockwise or counterclockwise obliquely or upright radially outward extending from the central portion, and the torque input section and the at least one compartment are located at the central portion, and the at least one torque output section is located at the at least one arm portion.

In yet another aspect of the present invention, the number of the at least one arm portion is plural, and the arm portions are formed at uneven pitches.

In yet another aspect of the present invention, the central portion further comprises a flange which is formed on an edge of the central portion, and the at least one arm portion is clockwise or counterclockwise obliquely or upright radially outward extending from the flange.

In yet another aspect of the present invention, an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.

In yet another aspect of the present invention, the at least one gauge is attached on a flat surface of the spider, and a normal line of the flat surface forms an angle with a plane of the chainring and the angle ranges from 0 to 180 degrees.

In yet another aspect of the present invention, the flat surface of the spider is formed on a convex or concave of the spider and aligned with the tangential direction or the quasi-tangential direction.

In yet another aspect of the present invention, the at least one compartment includes at least one accommodating space and at least one sidewall surrounding the at least one accommodating space, and wherein the central portion further comprises at least one bridge connecting the torque input section to the flange, and wherein an edge of the at least one bridge is formed to be a part of an edge of the accommodating space, and wherein the at least one gauge is disposed on the at least one bridge, the flange or the at least one arm portion.

In yet another aspect of the present invention, the at least one compartment accommodates the circuitry and/or at least one power source powering the circuitry.

In yet another aspect of the present invention, a spider comprises a central portion including a torque input section, a flange and at least one bridge connecting the torque input section to the flange; at least one arm portion including at least one torque output section and outward extending from the flange; at least one compartment located between the torque input section and the at least one torque output section, the at least one compartment including: at least one sidewall; and at least one accommodating space, surrounded by the at least one sidewall; and at least one gauge disposed on the at least one bridge, the flange or the at least one arm portion and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section and generating a signal in response to torque transmission from the torque input section to the at least one torque output section, wherein an edge of the at least one bridge is formed to be a part of an edge of the accommodating space.

In yet another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent or an internal common tangent to the torque input section and the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the tangential direction is defined as a direction along an external common tangent and an internal common tangent to a circle with a radius of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section and a circle with a radius of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.

In yet another aspect of the present invention, the number of the at least one arm portion is plural, and the arm portions are formed at uneven pitches.

In yet another aspect of the present invention, the at least one accommodating space is at least one opening or cavity, and the at least one bridge is clockwise or counterclockwise obliquely or upright radially extending from the torque input section and connecting to the flange.

In yet another aspect of the present invention, an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.

In yet another aspect of the present invention, the at least one gauge is attached on a flat surface of the spider, and a normal line of the flat surface forms a first angle with a main plane of the spider and the first angle ranges from 0 to 180 degrees.

In yet another aspect of the present invention, the flat surface of the spider is formed on a first face of the at least one bridge.

In yet another aspect of the present invention, a recession is formed on a second face of the at least one bridge opposite to the first face.

In yet another aspect of the present invention, the normal line of the flat surface forms a second angle with a main plane of the recession and the second angle ranges from 0 to 180 degrees.

In yet another aspect of the present invention, the number of the at least one bridge is different from the number of the at least one arm portion.

These and other features and advantages of the present invention can be more readily understood from the following preferred embodiments of the present invention with reference to the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to sufficiently understand the essence, advantages and the preferred embodiments of the present invention, the following detailed description will be more clearly understood by referring to the accompanying drawings.

FIG. 1 depicts a bicycle capable of measuring power generated from a cyclist in accordance with one embodiment of the present invention.

FIG. 2 depicts a view of the assembly particularly including a spider partially enlarged from the bicycle of FIG. 1.

FIG. 3A depicts another view of the spider in FIG. 2.

FIG. 3B depicts a variation on the spider of FIG. 3A.

FIG. 3C depicts another variation on the spider of FIG. 3A.

FIG. 3D depicts another variation on the spider of FIG. 3A.

FIG. 3E depicts another variation on the spider of FIG. 3A.

FIG. 3F depicts another variation on the spider of FIG. 3A.

FIG. 3G depicts another variation on the spider of FIG. 3A.

FIG. 3H depicts another variation on the spider of FIG. 3A.

FIG. 3I depicts another variation on the spider of FIG. 3A.

FIG. 3 depicts another variation on the spider of FIG. 3A.

FIG. 4 depicts an external common tangent and an internal common tangent to the torque input section and torque output section of the spider in FIG. 3A.

FIGS. 5A-5B depict various external common tangents and internal common tangents to the torque input section and torque output section in FIG. 3A.

FIG. 6A depicts a view of a spider with a concave in accordance with yet another embodiment of the present invention.

FIG. 6B depicts a cross-sectional view of the concave in accordance with the spider of FIG. 6A.

FIG. 6C depicts a cross-sectional view of the concave in accordance with the spider of FIG. 6A.

FIG. 6D depicts a cross-sectional view of the central portion including the torque input section, the flange and the bridge in accordance with the spider of FIG. 3G or 3H.

FIG. 6E depicts a cross-sectional view of the central portion including the torque input section, the flange and the bridge in accordance with the spider of FIG. 3G or 3H.

FIG. 7A depicts a view of a spider with a convex in accordance with yet another embodiment of the present invention.

FIG. 7B depicts a cross-sectional view of the convex in accordance with the spider of FIG. 7A.

FIG. 7C depicts a cross-sectional view of the convex in accordance with the spider of FIG. 7A.

FIG. 8A depicts a view of a spider with a flat surface in accordance with yet another embodiment of the present invention.

FIG. 8B depicts a cross-sectional view of the flat surface in accordance with the spider of FIG. 8A.

FIG. 9A depicts a view of a spider with a flat surface in accordance with yet another embodiment of the present invention.

FIG. 9B depicts an enlarged view of the flat surface in accordance with the spider of FIG. 9A.

FIG. 10A depicts a view of a spider with a concave in accordance with yet another embodiment of the present invention.

FIG. 10B depicts a cross-sectional view of the concave in accordance with the spider of FIG. 10A.

DETAILED DESCRIPTION OF THE DRAWINGS

The following description shows the preferred embodiments of the present invention. The present invention is described below by referring to the embodiments and the figures. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the principles disclosed herein. Furthermore, that various modifications or changes in light thereof will be suggested to a person having ordinary skill in the art and are to be included within the spirit and purview of this application and scope of the appended claims.

Now refer to FIGS. 1, 2 and 3A-J. FIG. 1 depicts a bicycle (1) capable of measuring power generated from a cyclist according to one embodiment of the present invention, FIG. 2 depicts an enlarged view of the assembly particularly including a spider (10) partially enlarged from the bicycle (1) of FIG. 1, FIG. 3A depicts another view of the spider (10) in FIG. 2, and FIGS. 3B-J depict variations on the spider of FIG. 3A. The bicycle (1) is equipped with two pedals (50-1, 50-2) and two crank arms (20-1, 20-2). The pedals (50-1, 50-2) are respectively mounted to one ends of the corresponding crank arms (20-1, 20-2), and both of them are mounted to a crank axle (20-3) at the other ends. When a cyclist rides on the bicycle (1), the two pedals (50-1, 50-2) are applied by foot force during a reciprocating motion of the cyclist's legs. The force is applied to one end of each crank arms (20-1, 20-2) and generates torque to the other end of each crank arms (20-1, 20-2) which is connected to the crank axle (20-3). The two crank arms (20-1, 20-2) and the crank axle (20-3) are collectively called as a crank assembly (20).

The spider (10) includes a torque input section (101) and five torque output sections (102) as shown in FIG. 2. The crank assembly (20) is coupled with the spider (10) through the torque input section (101), and two chainrings (30-1, 30-2) are mounted to the spider (10) through the torque output sections (102) by any fastening means. From the perspective of the spider (10), the spider (10) receives the torque from the crank assembly (20) through the torque input section (101) and transmits the torque to one of the chainrings (30-1, 30-2) through the torque output sections (102). The chosen one of the chainrings (30-1, 30-2) transmit the torque from the torque output sections (102) to the chain for overcoming or exceeding the opposing force of friction from the bicycle tires and the air resistance (not shown in FIG. 2).

Even though the two chainrings (30-1, 30-2) are illustrated in FIG. 2 in accordance with the present embodiment of the present invention, a person having ordinary skill in the art may understand that the number of chainrings may be varied based on different demands from consumers or manufacturers.

Referring to FIG. 3A, the spider (10) has five arm portions (112) and a central portion (111). The torque input section (101) is located at the central portion (111) and the five torque output sections (102) are located at the five arm portions (112). As shown in FIG. 3A, each arm portion (112) is asymmetric with respect to a line (L) from a center of the torque input section (101) to a center of the corresponding torque output section (102). As shown in FIG. 3A as well, the five arm portions (112) do not radially extend from the central portion (111). More specifically, the arm portions (112) are counterclockwise obliquely extending from the central portion (111) in the front view of the spider (10). The arm portions (112) are defined as an external common tangent (ECT) to the torque input section (101) and any torque output section (102) forms an angle (A) with the line (L) from a center of the torque input section (101) to a center of the corresponding torque output section (102) and the angle (A) ranges from 3 to 75, preferably 30 to 45, degrees.

It should be noted that the present application is not limited to the embodiment in FIG. 2. A person having ordinary skill in the art may understand that any number of torque output section (102) and arm portion (112) may be varied based on different demands from consumers or manufacturers. For example, an odd number of torque output section (102) and arm portion (112), such as FIGS. 3A-3D and 3G-3H, or an even number of torque output section (102) and arm portion (112), such as FIGS. 3E-3F and 3I-3J, is designable for different demands from consumers or manufacturers. A person having ordinary skill in the art may also understand that the arm portions (112) may not only be formed at even pitches, such as the spiders (10, 10 p, 10 r, 10 t) shown in FIGS. 3A-3D, 3G-3H and 3I-3J, but also be formed at uneven pitches, such as the spider (10 q) shown in FIGS. 3E-3F.

It should be noted that the arm portions (112) are counterclockwise obliquely extending from the central portion (111) in the front view of the spider (10) illustrated in FIG. 3A in accordance with the present embodiment of the present invention. A person having ordinary skill in the art may understand that the arm portions (112) may be designed to be clockwise obliquely extending from the central portion (111) in the front view of the spider (10, 10 p, 10 q, 10 r), as illustrated in FIGS. 3B, 3D, 3F and 3H, or upright radially extending from the central portion in the front view of the spider (not shown).

Furthermore, under certain circumstances, there is a need to reduce the weight of the bicycle (1) because a lightweight bicycle usually makes a cyclist ride faster. In other words, in pursuit of faster cycling speed, it is desirable to reduce the weight of all kinds of parts of the bicycle. Referring to FIGS. 3C-3D, the central portion (111) of the spider (10 p), comparing to FIGS. 3A-3B, further comprises five compartments (150) which are located between the torque input section (101) and the five torque output sections (102). The five compartments (150) include five accommodating spaces (172) and five sidewalls (173). More specifically, each of the compartments (150) may be a closed compartment, including an accommodating space (172) and a cover (not shown) or an open compartment, such as a hollow opening (172) or a non-hollow cavity (172), formed by cutting, forging or casting on the spider (10 p).

It should be noted that though, in FIG. 3C, the non-hollow cavities (172) are formed on a front face of the spider (10 p), a person having ordinary skill in the art may understand that the non-hollow cavities (172) may also be formed on a back face or a side face of the spider (10 p). One example, where the non-hollow cavities (172) are formed on the back face, is illustrated in FIG. 6C, 6D, 6E or 7C and will be introduced as recessions (181) and described in detail later.

In another embodiment, referring to FIGS. 3G-3H, the central portion (111) of the spider (10 r), comparing to FIGS. 3A-3B, further comprises five compartments (150), five bridges (171) and a flange (161). The flange (161) is formed on an edge of the central portion (111). The five compartments (150) are located between the torque input section (101) and the flange (161). The flange (161) is located between the five compartments (150) and the five torque output sections (102). The five bridges (171) connect the torque input section (101) to the flange (161), and more specifically, the five bridges (171) are clockwise or counterclockwise obliquely or upright radially extending from the torque input section (101) and connecting to the flange (161). The compartments (150) include five sidewalls (173) and five accommodating spaces (172). Structurally speaking, the five accommodating spaces (172) are surrounded by the five sidewalls (173) which are formed by the torque input section (101), the flange (161) and the five bridges (171). That is, an edge of the torque input section (101), an edge of the flange (161) and edges of the five bridges (171) compose edges of the five accommodating spaces (172).

It should be noted that though, in FIG. 3G or 3H, the edges of the five accommodating spaces (172) are composed of an edge of the torque input section (101), an edge of the flange (161) and edges of the five bridges (171), a person having ordinary skill in the art may understand that, depending on the designed position and size of the accommodating spaces (172), the edges of the five accommodating spaces (172) may be composed by an edge of the torque input section (101) and edges of the five bridges (171) in one practice, or by an edge of the flange (161) and edges of the five bridges (171) in another practice, or merely by edges of the five bridges (171) in yet another practice.

It should be noted that though, in FIG. 3G or 3H, the number of the bridges (171) is the same with that of arm portions (112), a person having ordinary skill in the art may understand that the number of the bridges (171) may be lower or higher than that of arm portions (112). For example, the number of the arm portions (112) may be four, however, the number of the bridges (171) may be two, three or five, such as the spider (10 t) illustrated in FIGS. 3I-3J, wherein the number of the arm portions (112) is four, and the number of the bridges (171) is five. The spider (10 t) in FIG. 3I, comparing to the spider (10 r) in FIG. 3G or 3H, the number of the arm portions (112) and torque output sections (102) is reduced by one. Besides, the spider (10 t) in FIG. 3J, comparing to the spider (10 t) in FIG. 3I, the arm portions (112) are upright radially extending from the flange (161) up to a longer distance.

Still referring to FIGS. 3G-3H, the flange (161) is generally annular in shape and may be formed to have a wall vertically extending from a main plane of the spider (10 r) in order to strength the stiffness of the spider (10 r). Further referring to FIGS. 3I-3J, the flange (161) is generally annular in shape and may be formed to have a wall vertically extending from a main plane of the spider (10 t) in order to strength the stiffness of the spider (10 t). Besides, in the front view, the flange (161) of the spider (10 t) in FIG. 3I or FIG. 3J has a width wider than that of the spider (10 r) in FIG. 3G or FIG. 3H, and such design causes torque to be efficiently transmitted to the torque output sections (102) of the spider (10 t). More specifically, the torque is transmitted from the torque input sections (101) to the torque output sections (102) via the bridges (171) and the flange (161), and the torque transmitted via the bridges (171) and the flange (161) is more efficient with less wasted peddling effort if the bridges (171) and/or the flange (161) is designed to be wider in width in the front view of the spider (10 t).

It should be noted that, in FIG. 3G, 3H, 3I or 3J, the flange (161) is formed as being the wall, which is higher than the main plane of the spider (10 r, 10 t) in height. A person having ordinary skill in the art may understand that the height of the flange (161) may be formed to be lower than that of the main plane of the spider (10 r, 10 t) or of the same height as the main plane of the spider (10 r, 10 t) based on different demands from consumers or manufacturers.

As is illustrated in FIGS. 3A-3J, a gauge (40) is partially disposed on the central portion (111) and partially disposed on the at least one arm portion (112) and oriented generally along a tangential direction (TD) or a quasi-tangential direction (QTD) with respect to the torque input section (101) and the at least one torque output section (102). As is illustrated in FIGS. 3G-3J, a gauge (40) is disposed on the at least one bridge (171) and oriented generally along a tangential direction (TD) or a quasi-tangential direction (QTD) with respect to the torque input section (101) and the at least one torque output section (102). Generally speaking, the gauge (40) may be disposed on any flat surface, such as a flat surface on the central portion (111) or on the arm portion (112) depicted in FIGS. 3A-3F, or a flat surface on the bridge (171), the flange (161) or the arm portion (112) depicted in FIGS. 3G-3J.

The gauge (40), as an illustrative example, is a strain gauge. The strain gauge is a kind of sensor typically consisting of an insulating flexible base and a metallic foil pattern whose electrical resistance changes with applied force. The strain gauge is then attached to an object by any suitable adhesive. When force is applied to the object and causes deformation of the object, the metallic foil changes its electrical resistance with the deformation. The change in the electrical resistance is measured typically by a Wheatstone bridge. By the way, when the force is applied to an object, stress and strain occur. Stress is defined as an internal force of the object, and strain is defined as the internal deformation of the object occurs.

Upon the torque being applied to the spider (10, 10 p, 10 q, 10 r, 10 t), the gauge (40) is capable of measuring deformation of the spider (10, 10 p, 10 q, 10 r, 10 t) and generates an electronic signal in response to strength of the torque. In the case of FIG. 3A, 3C, 3E or 3G that the arm portions (112) are counterclockwise obliquely extending from the central portion (111) or the flange (161) in the front view of the spider (10, 10 p, 10 q, 10 r), pure tensile stress generated by the torque occurs on where the gauge (40) is disposed. On the contrary, in the case that the arm portions (112) are clockwise obliquely extending from the central portion (111) or the flange (161) in the front view of the spider (10, 10 p, 10 q, 10 r) as shown in FIG. 3B, 3D, 3F or 3H, pure compressive stress generated by the torque occurs on where the gauge (40) is disposed. In the case that the arm portions are upright radially extending from the central portion (111) or the flange (161) in the front view of the spider (10 t) as shown in FIGS. 3I-3J, pure tensile stress or pure compressive stress generated by the torque occurs on where the gauge is disposed. The electronic signal generated by the gauge (40) contains information representative of the strength of the pure tensile or compressive stress. The electronic signal is then transmitted to a circuitry (not shown in FIGS. 3A-3J) coupled to the gauge (40).

It should be noted that the accommodating spaces (172) of the compartments (150) shown in FIGS. 3C-3J or the generally annular space enclosed by the wall of flange (161) shown in FIGS. 3G-3J, which is higher than the main plane of the spider (10 r, 10 t) in height, may be used to accommodate some elements of the bicycle (1), such as the circuitry and/or at least one power source (not shown in FIGS. 3A-3J) powering the circuitry. In one practice, the circuitry and at least one power source are disposed in one accommodating space (172). In another practice, the circuitry is disposed in one accommodating space (172) and the power source is disposed in another accommodating space (172). In yet another practice, the circuitry, including a printed circuit board (PCB), is disposed in the space enclosed by the wall of flange (161) and the power source is disposed in one of the accommodating spaces (172) of the compartments (150).

It should be noted that though the gauge (40) is disposed on a front face of the spider (10, 10 p, 10 q, 10 r, 10 t) in accordance with the present embodiment of the present invention, a person having ordinary skill in the art may understand that the gauge (40) or plural gauges may be disposed on a back face or a side face of the spider (10, 10 p, 10 q, 10 r, 10 t).

It should be noted that though only one gauge (40) is illustrated in accordance with the present embodiment of the present invention, a person having ordinary skill in the art may understand that one or more gauges may be disposed. Generally speaking, the number of the gauge is equal or smaller than that of the arm portion or bridge. However, based on various designs and demands, the number of the gauge may be larger than that of the arm portion or bridge. For example, there may be two gauges disposed on each arm portion or bridge, such that the number of the gauge is twice that of the arm portion or bridge.

By disposing and orienting the gauge (40) generally along a tangential direction or a quasi-tangential direction with respect to the torque input section (101) and the at least one torque output section (102), the torque, or pedaling power during a period of time, may be easily derived in accordance with the present embodiment of the present invention.

FIG. 4 depicts an external common tangent (ECT) and an internal common tangent (ICT) to the torque input section (101) and torque output section (102) of the spider (10) in FIG. 3A. The tangential direction (TD) may be more specifically defined as a direction along an external common tangent (ECT) or an internal common tangent (ICT) to the torque input section (101) and the at least one torque output section (102). The quasi-tangential direction (QTD) may be more specifically defined as a direction along a line whose slope is between slopes of the external common tangent (ECT) and the internal common tangent (ICT) in accordance with another embodiment of the present invention. By disposing and orienting the gauge (40) generally along the tangential direction (TD) or the quasi-tangential direction (QTD) depicted in FIG. 4, the torque, or pedaling power during a period of time, may be simply, precisely and accurately measured.

FIGS. 5A and 5B both show various external common tangents (ECT) and internal common tangents (ICT) to the torque input section (101) and torque output section (102) in FIG. 3A. The tangential direction (TD) may also be more specifically defined as a direction along an external common tangent (ECT) and an internal common tangent (ICT) to a circle with a radius (R) of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section (101) and a circle with a radius (r) of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section (102). The quasi-tangential direction (QTD) may also be more specifically defined as a direction along a line whose slope is between slopes of the external common tangent (ECT) and the internal common tangent (ICT). For illustrative purpose, FIG. 5A depicts that the radius R is 30 millimeters and the radius r is 5 millimeters and FIG. 5B depicts that radius R is 50 millimeters and radius r is 6 millimeters in accordance with yet another embodiment of the present invention. By disposing and orienting the gauge (40) generally along the tangential direction (TD) or the quasi-tangential direction (QTD) depicted in FIG. 5A or 5B, the torque, or pedaling power during a period of time, may be simply, precisely and accurately measured.

It should be noted that x and y axes are not indicated in FIGS. 4, 5A and 5B because the spider (10) is rotatable. However, the slopes of the tangential direction (TD) and the quasi-tangential direction (QTD) can be understood as steepness of lines in relative terms.

Now refer to FIG. 6A depicting a front view of the spider (10 s) with at least one concave (120) in accordance with yet another embodiment of the present invention. The at least one concave (120) of the spider (10 s) has an inclined flat surface (121). The gauge (40) is attached on the inclined flat surface (121) of the at least one concave and aligned with the tangential direction (TD) or the quasi-tangential direction (QTD) with respect to the torque input section (101) and the corresponding torque output section (102). FIG. 6B depicts a cross-sectional view of the concave in accordance with the spider of FIG. 6A. The inclined flat surface (121) has an inclined angle with the main plane of the central portion (111). Compared with the present embodiment, FIGS. 10A-10B illustrate that a spider (10 a) has at least one concave (120 a) with two side flat surfaces (121 a and 121 c) and a bottom flat surface (121 b), and the side flat surfaces (121 a and 121 c) is perpendicular to a main plane of the central portion (111), and the bottom flat surface (121 b) is parallel to the main plane of the central portion (111).

It should be noted that though the gauge (40) is attached on the inclined flat surface (121) or the side flat surface (121 a) of the at least one concave in accordance with the embodiments of the present invention shown in FIGS. 6A-6B and 10A-10B, a person having ordinary skill in the art may not only understand that the gauge (40) may be attached on the side flat surface (121 c) or the bottom flat surface (121 b) but also understand that the spider may be designed as to have at least one convex (130) with an inclined flat surface (131) or a side flat surface (not shown) to which the gauge (40) is attached, such as a spider (10 b) shown in FIGS. 7A and 7B. Moreover, the gauge (40) may also be attached to anywhere of the spider as long as a flat surface could be found, such as a flat surface (141) could be found from a front face of a spider (10 c) as shown in FIGS. 8A and 8B and another flat surface (151) could be found from a side face of the spider (10 c) as shown in FIGS. 9A and 9B. In short summary, the flat surface (121, 121 a, 121 b, 121 c, 131, 141 and 151) of the spider (10 s, 10 a, 10 b and 10 c) or the attached area in accordance of these embodiments is broadly defined in a manner that a normal line (N) of the flat surface (121, 121 a, 121 b, 121 c, 131, 141 and 151) or the attached area forms an angle (B) with a plane of any chainring (illustrated by numeral reference 30-1 only) which is parallel to a main plane of the spider (10 s, 10 a, 10 b and 10 c) and the angle (B) ranges from 0 to 180 degrees. A line (P) depicted in FIGS. 6A-10B lies on the plane of the chainring (30-1) and is used to illustrate where the plane of the charning (30-1) is.

For these exemplary embodiments, in FIGS. 9A-9B, the gauge (40) is directly attached on the side face of the spider (10 c) so that the angle (B) is 0 degree. In FIGS. 7A-7B, the gauge (40) is attached on the inclined flat surface (131) of the convex (130) of the spider (10 b), and the angle (B) ranges from 0 to 90 degrees. In FIGS. 8A-8B, the angle (B) is 90 degrees when the gauge (40) is directly attached on the front or back face of the spider (10 c). In FIGS. 6A-6B and 10A-10B, the gauge (40) is attached on the inclined flat surface (121) or the side flat surface (121 a) of the concave (120, 120 a) of the spider (10 s, 10 a), the angle (B) ranges from 90 to 180 degrees.

Furthermore, it should also be noted that sometimes there is a need to reduce the weight of the bicycle (1) as described above. Accordingly, in one embodiment, FIG. 6C or 7C depict a cross-sectional view of the concave (120) or the convex (130) in accordance with the spider of FIG. 6A or 7A. A recession (181) may be formed under the concave (120) or the convex (130). Structurally speaking, when the concave (120) or the convex (130) is formed on a first face of the spider, there is still room for a recession (181) to be correspondingly emptied on a second face of the spider opposite to the first face. The recession (181) may be formed in any suitable profiles, such as a wedge-shaped one which is a profile corresponding to the profile of the convex (130) or the concave (120). Specifically, as illustrated in FIGS. 6C and 7C, the normal line (N) of the flat surface (121, 131) forms an angle (C) with a main plane (331) of the recession (181) and the angle (C) ranges from 0 to 180 degrees. In other words, the flat surface (121, 131) and the main plane (331) of the recession (181) may be parallel or not parallel to each other and if the flat surface (121, 131) and the main plane (331) of the recession (181) are parallel, the angle (C) would be 90 degrees.

In another embodiment, FIG. 6D or 6E depict a cross-sectional view of the torque input section (101), the flange (161) and the bridge (171) in accordance with the spider (10 r, 10 t) depicted in FIG. 3G, 3H, 3I or 3J. A recession (181) may be formed under the bridge (171). Structurally speaking, the bridge (171) connects the torque input section (101) to the flange (161) and forms a passage for the torque to pass through. A flat surface (221, 231) may be formed on a first face of the bridge (171) for the gauge (40) to be attached on. A normal line (N) of the flat surface (221, 231) forms a first angle (B) with a main plane of the spider (10 r) and the first angle (B) ranges from 0 to 180 degrees. When the flat surface (221, 231) is formed on the first face of bridge (171), there is still room for a recession (181) to be correspondingly emptied on a second face of the bridge (171) opposite to the first face of bridge (171). Specifically, as illustrated in FIGS. 6D and 6E, the normal line (N) of the flat surface (221, 231) forms a second angle (C) with a main plane (331) of the recession (181) and the second angle (C) ranges from 0 to 180 degrees. In other words, the flat surface (221, 231) and the main plane (331) of the recession (181) may be parallel or not parallel to each other and if the flat surface (221, 231) and the main plane (331) of the recession (181) are parallel, the second angle (C) would be 90 degrees.

Broadly speaking, it should be noted that a person having ordinary skill in the art may understand that the gauge (40) may be alternatively attached on the main plane (331) of the recession (181) because the main plane (331) of the recession (181) is also a kind of flat surface of the spider (10 b, 10 s, 10 r, 10 t).

It should also be noted that the wall of flange (161) shown in FIG. 6E is higher than the main plane of the spider (10 r, 10 t) in height and the generally annular space enclosed by the wall of flange (161) may be used to store some elements of the bicycle (1), whereas the flange (161) shown in FIG. 6D is of the same height as the main plane of the spider (10 r, 10 t).

The preferred embodiments of the present invention have been described above. However, those having ordinary skill in the art readily recognize that the disclosure described above can be utilized in a variety of devices, environments, and situations. Although the present invention is written with respect to specific embodiments and implementations, various changes and modifications may be suggested to a person having ordinary skill in the art. It is intended that the present disclosure encompass such changes and modifications that fall within the scope of the appended claims. 

1. A bicycle, comprising: a spider including a torque input section, at least one torque output section, and at least one compartment which is located between the torque input section and the at least one torque output section; a crank assembly coupled with the spider through the torque input section and applying an input torque to the spider; a chainring mounted to the spider through the at least one torque output section and receiving an output torque from the spider; at least one gauge disposed and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section; and a circuitry coupled to the at least one gauge and receiving a signal from the at least one gauge.
 2. The bicycle of claim 1, wherein the tangential direction is defined as a direction along an external common tangent or an internal common tangent to the torque input section and the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.
 3. The bicycle of claim 1, wherein the tangential direction is defined as a direction along an external common tangent and an internal common tangent to a circle with a radius of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section and a circle with a radius of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.
 4. The bicycle of claim 1, wherein the spider has a central portion and at least one arm portion which is clockwise or counterclockwise obliquely or upright radially outward extending from the central portion, and the torque input section and the at least one compartment are located at the central portion, and the at least one torque output section is located at the at least one arm portion.
 5. The bicycle of claim 4, wherein the number of the at least one arm portion is plural, and the arm portions are formed at uneven pitches.
 6. The bicycle of claim 4, wherein the central portion further comprises a flange which is formed on an edge of the central portion, and the at least one arm portion is clockwise or counterclockwise obliquely or upright radially outward extending from the flange.
 7. The bicycle of claim 6, wherein an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.
 8. The bicycle of claim 1, wherein the at least one gauge is attached on a flat surface of the spider, and a normal line of the flat surface forms an angle with a plane of the chainring and the angle ranges from 0 to 180 degrees.
 9. The bicycle of claim 8, wherein the flat surface of the spider is formed on a convex or concave of the spider and aligned with the tangential direction or the quasi-tangential direction.
 10. The bicycle of claim 6, wherein the at least one compartment includes at least one accommodating space and at least one sidewall surrounding the at least one accommodating space, and wherein the central portion further comprises at least one bridge connecting the torque input section to the flange, and wherein an edge of the at least one bridge is formed to be a part of an edge of the accommodating space, and wherein the at least one gauge is disposed on the at least one bridge, the flange or the at least one arm portion.
 11. The bicycle of claim 10, wherein the at least one compartment accommodates the circuitry and/or at least one power source powering the circuitry.
 12. A spider, comprising: a central portion including a torque input section, a flange and at least one bridge connecting the torque input section to the flange; at least one arm portion including at least one torque output section and outward extending from the flange; at least one compartment located between the torque input section and the at least one torque output section, the at least one compartment including: at least one sidewall; and at least one accommodating space, surrounded by the at least one sidewall; and at least one gauge disposed on the at least one bridge, the flange or the at least one arm portion and oriented generally along a tangential direction or a quasi-tangential direction with respect to the torque input section and the at least one torque output section and generating a signal in response to torque transmission from the torque input section to the at least one torque output section, wherein an edge of the at least one bridge is formed to be a part of an edge of the accommodating space.
 13. The spider of claim 12, wherein the tangential direction is defined as a direction along an external common tangent or an internal common tangent to the torque input section and the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.
 14. The spider of claim 12, wherein the tangential direction is defined as a direction along an external common tangent and an internal common tangent to a circle with a radius of 10 to 100, preferably 30 to 45, millimeters from a center of the torque input section and a circle with a radius of 4 to 6, preferably 5, millimeters from a center of the at least one torque output section, and the quasi-tangential direction is defined as a direction along a line whose slope is between slopes of the external common tangent and the internal common tangent.
 15. The spider of claim 12, wherein the number of the at least one arm portion is plural, and the arm portions are formed at uneven pitches.
 16. The spider of claim 12, wherein the at least one accommodating space is at least one opening or cavity, and the at least one bridge is clockwise or counterclockwise obliquely or upright radially extending from the torque input section and connecting to the flange.
 17. The spider of claim 12, wherein an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.
 18. The spider of claim 16, wherein the at least one gauge is attached on a flat surface of the spider, and a normal line of the flat surface forms a first angle with a main plane of the spider and the first angle ranges from 0 to 180 degrees.
 19. The spider of claim 18, wherein the flat surface of the spider is formed on a first face of the at least one bridge.
 20. The spider of claim 19, wherein a recession is formed on a second face of the at least one bridge opposite to the first face.
 21. The spider of claim 20, wherein the normal line of the flat surface forms a second angle with a main plane of the recession and the second angle ranges from 0 to 180 degrees.
 22. The spider of claim 12, wherein the number of the at least one bridge is different from the number of the at least one arm portion.
 23. The bicycle of claim 4, wherein an external common tangent to the torque input section and the at least one torque output section forms an angle with a line from a center of the torque input section to a center of the at least one torque output section and the angle ranges from 3 to 75, preferably 30 to 45, degrees.
 24. The bicycle of claim 1, wherein the at least one compartment accommodates the circuitry and/or at least one power source powering the circuitry. 